Back to Square One - advice

[dlcatftwin]

Greetings all,
I am currently enjoying

Back to Square 1

.
I am in room 16404 - I am standing on the right side of the stair case (or ladder well if you will) past the zapper, and no where to go. What's my next move, please?
FYI, Jack's picked up so many keys (on the

hardest

route) that he wasn't able to pick up the blue key in the prior room.
Is it needed in Rm. 16404?
Many thanks,
DLC  :-X

[brell]

Hi!  Just jump onto the picture.

I don't understand how you managed to fill up your inventory so you couldn't get the blue key.  It is needed later.  Have you already done the easy and normal route?  What did you hav ein your inventory when you entered room #16403?

EDIT:  You ARE on the hardest route.  There is only ONE (red) key on that route before room #16403 so I don't where all your keys came from. You should indeed have used that red key before you came to #16403 so you should be out of keys by then.